How to Stretch Canvas
You can buy stretcher bars at most art shops, hobby shops or online (type “stretcher bars” in to the internet search box) Buy stretcher bars to the size of your image.
Step 1: Slot together the stretcher frame. Use a rubber hammer to insure the corners fit tightly.
Step 2: Cut canvas large enough to fold around stretcher edge and cover stretcher bar.
For purposes of this demonstration we will refer to the positions on the square stretcher as north, east, south and west.
Step 3: Begin attaching canvas to frame. Choose a side to begin with (we'll begin in the east position) and place the first staple in the center of the stretcher bar. Begin using the canvas pliers on the opposite stretcher bar, west position, also starting in the center. Pull canvas taught.
If you are working in a size larger than 3' x 3' it is recommended that cross braces are added to support your frame. Additional cross braces should be added incrementally as your canvas size increases. Have a custom frame size?
Regular and Heavy duty.
Dozens of sizes!
Step 4: Continue with the pliers in the center of the north position, then again in the south position. Once the center points are secure, you will complete the stretching process by methodically moving from one position to the other, as follows.
This process insures even tension on the canvas beams and is essential to achieve a taught, firm painting surface.
Step 5: Returning to your starting point in the east position, pull the canvas taught using your canvas pliers. Using the staple gun, place staples about 2 inches apart. Stretch and place 2 staples on each side of the center staple. Cross over to the west position and repeat. Continue in this manner in the north and south position.
Step 6: Return to the east position and continue in the same manner, spreading out incrementally from the center position, working around the canvas progressively until you are within 3 to 4 inches from the corners.
Step 7: Once the canvas is attached to the frame excess fabric should be trimmed away from the back.
Step 8: Finishing the corners: pull corner of canvas tightly across the back of the stretcher towards the center.
Step 9: Fold one of the canvas wings in and over.
Step 10: Fold the second wing of canvas in and position it over the first wing
Step 11: Secure the fold to the stretcher using your staple gun.
Step 12: Add hangers and you are finished!
If your canvas is still slightly loose you can add wedges in the interior corners of your stretcher bars, spreading them slightly apart and making your canvas more taught.